Triton Naval Architects
  Salvage Photos

services / ship salvage / helderberg


The S.A. Helderberg expereinced a collision at sea, whereby an Oil Tanker hit her on the stbd side oppoiste the engine room, off Singapore in Feb 2007.

She was holed through the wing tanks, with controllable water ingress into the engine room. The superstructure off the Mess Room was also holed.

We were called in by the Salavage Company SVITZERWIJSMULLER to design a cofferdam so as to isolate the engine room from further water ingress, to allow the vessel to come into port and discharge, before a full repair could be undertaken in dry dock.

The cofferdam was 15m wide and 11m high, designed as an offset box structure with internal strengthening, (largely from a Hotel Room in Singapore, with draughting support from back in SA). The design accomodated divers operating inside. The tricky aspect was that all three of the contact edges were on different curvatures, hence the shape had to be accurate with little fabrication tolerance. The cofferdam was built by PM COAST (S) PTE LTD in Singapore, and transported by barge to the awaiting vessel.

The cofferdam was fitted by Svitzerwijsmuller.

The cofferdam, once seated and sealed, ended up giving a total seal, and was considered a great success.


Triton Naval Architects
No. 8 Foregate Square, Harbour Rd
Foreshore, Cape Town, SOUTH AFRICA
Tel: +27 21 418 2090 | Fax: +27 21 425 2722 | Email:

By Triton Naval Architects




Helderberg holed on ER Wing Bunker Tanks, and Super Structure above.


Close up of side damage. ER longitudinal bulkhead largly intact, with small water ingress.


Fabricated Cofferdam being lifted into place during installation. A 24hr operation.


Cofferdam in place, being sealed up against the mating hull surfaces.